## Abstract

We present computationally efficient and accurate semiempirical models of light transfer suitable for real-time diffuse reflectance spectroscopy. The models predict the diffuse reflectance of both (i) semi- infinite homogeneous and (ii) two-layer media exposed to normal and collimated light. The two-layer medium consisted of a plane-parallel slab of finite thickness over a semi-infinite layer with identical index of refraction but different absorption and scattering properties. The model accounted for absorption and anisotropic scattering, as well as for internal reflection at the medium/air interface. All media were assumed to be nonemitting, strongly forward scattering, with indices of refraction between 1.00 and 1.44 and transport single-scattering albedos between 0.50 and 0.99. First, simple analytical expressions for the diffuse reflectance of the semi-infinite and two-layer media considered were derived using the two-flux approximation. Then, parameters appearing in the analytical expression previously derived were instead fitted to match results from more accurate Monte Carlo simulations. A single semiempirical parameter was sufficient to relate the diffuse reflectance to the radiative properties and thickness of the semi- infinite and two-layer media. The present model can be used for a wide range of applications including noninvasive diagnosis of biological tissue.

© 2009 Optical Society of America

Full Article | PDF Article**OSA Recommended Articles**

Dmitry Yudovsky and Laurent Pilon

Appl. Opt. **49**(10) 1707-1719 (2010)

Dmitry Yudovsky and Laurent Pilon

Appl. Opt. **49**(31) 6072-6084 (2010)

Hong Qi, Ya-Tao Ren, Qin Chen, and Li-Ming Ruan

Appl. Opt. **54**(16) 5234-5242 (2015)